1. Field of the Invention
The present invention relates to means for engaging and securing the column of chromatography apparatus to a given support and, more especially, to securing the column to its injection head or moving phase/sample inlet cap, or to the inlet for filling the column itself.
The column chromatography apparatus may be a gas or a liquid/column chromatography apparatus.
2. Description of the Prior Art
A column chromatography apparatus of known type typically successively comprises, in the direction of flow:
(I) A CARRIER RESERVOIR;
(II) A CARRIER SYSTEM, WHICH CONVEYS SAID CARRIER TO THE SEPARATION COLUMN;
(III) A HEAD FOR INJECTING THE CARRIER INTO THE SEPARATION COLUMN;
(IV) MEANS FOR INJECTING THE SAMPLE TO BE ANALYSED;
(V) A SEPARATION COLUMN WHEREIN THE ANALYSIS OR PREPARATIVE SEPARATION TAKES PLACE, E.G., WHERE THE SAMPLE IS SEPARATED INTO ITS VARIOUS CONSTITUENTS, SAID COLUMN BEING FILLED WITH A CONTINUOUS OR STATIONARY PHASE, E.G., A PARTICULATE ADSORBENT, PACKING OR SUBSTRATE; AND
(VI) A DETECTOR, SELECTED DEPENDING UPON THE NATURE OF THE MOLECULES TO BE DEVELOPED.
The performance of a chromatography column is affected by the geometry of the various components of the injection head/column assembly, in particular by the presence of dead space, and also by the precision of the injection of the sample to be analyzed into the top of the column.
In the usual instrument, the sample injection system (whether it be of syringe-and-membrane type, or operating by means of a valve with a sampling loop) and the column for separation are separate and distinct entities, being connected to each other by means of any suitable coupling invariably comprising a significant dead volume. Such a coupling is usually by clamping by means of a sleeve or of a sleeve and collar acting in concert, not uncommonly resulting in crimping of the sleeve or, more often, causing permanent deformations in the walls of the separation column. These deformations make it difficult or even impossible to ultimately fixedly mount the separation column to another member, instrument, or support. In addition to this lack of operational flexibility, such approach mandates that same or all of the couplings be replaced with each new installation; often, complete replacement of the separation column is required.
Similar couplings are also used to secure the separation column to its feed inlet, namely, to the means for filling the column with the continuous or stationary phase, commonly a particulate, differential adsorbent.